A man in constant need of nurturing and attention. The manbaby thinks his problems are fascinating and far more important and tragic than anyone else's. He cannot handle rejection in any form and will lament every breakup he has had throughout his lifetime, and cry over how he was mistreated by women decades in the past.

Susan: Why is Peter crying?

Elaine: He was just telling us about a girl he took out once in 1987 who didn't like him that much.

A guy who tries so desperately hard to be a "man," that he ends up internalizing all of his "unmanly" emotions. The end result is a flailing shitshow the second he realizes he's actually a vulnerable human being.

My man-baby of an ex called me for emotional support at 3 am last night after our break up, even though he broke up with me.